The presence of gut flora in the intestines may cause health benefits for some people, whereas it increases the risk of obesity in the others, researchers have claimed.

While sourcing a new link between gut bacteria and obesity, the animal based study found that certain amino acids in our blood can be connected to both obesity and the composition of the gut microbiome. Obesity-related metabolites were linked to four different intestinal bacteria namely Blautia, Dorea and Ruminococcus in the Lachnospiraceae family, and SHA98, the researchers noted.

The study, published in the Journal of Clinical Endocrinology and Metabolism, mentioned that the gut microbiota affects our metabolism and lead to cardiovascular diseases and Type 2 diabetes. Previous studies have shown that people with these diseases have varying occurrence of different metabolites, that is small molecules or metabolic residues, in the bloodstream.

The researchers analysed blood plasma and stool samples from 674 participants in the Malmö Offspring Study (MOS). They found 19 different metabolites that could be linked to the person's body mass index (BMI); glutamate and so-called BCAA (branched-chain and aromatic amino acids) had the strongest connection to obesity.

"The differences in BMI were largely explained by the differences in the levels of glutamate and BCAA. This indicates that the metabolites and gut bacteria interact, rather than being independent of each other," said Marju Orho-Melander, Professor at Lund University in Sweden. Previous studies have also shown that the manipulation in the gut bacteria may cut down diabetes, bowel diseases and obesity risk.